Evaluation of the 18-month "Pilot Study of Newborn Screening for Inborn Errors of Metabolism" in Hong Kong

Introduction: After the release of the Chief Executive's 2015 Policy Address in Hong Kong, a pilot study was planned and implemented to study the feasibility of trying out in the public healthcare system a screening programme for newborn babies for inborn errors of metabolism (IEM). After six months of preparation, the "Pilot Study of Newborn Screening for Inborn Errors of Metabolism" was launched in October 2015 in two public birthing hospitals (Queen Elizabeth Hospital and Queen Mary Hospital). It lasted for 18 months in two phases: Phase I from October 2015 to March 2016 (covering 21 IEM diseases) and Phase II from April 2016 to March 2017 (covering totally 24 IEM diseases). Aim: This paper is to review the course of events and discuss about the clinical findings of the Pilot Study. Results and conclusion: The Pilot Study had been operated smoothly, in aspects of parental education, specimen collection, preparation and dispatch of specimens. There were effective communication and cooperation among different parties involved in baby recall, arrangement of further investigations and clinical management. 15,138 out of 15,361 (98.5%) eligible babies had parental written consents to join the Pilot Study and 9 IEM cases were confirmed (incidence of the Pilot Study was 1 in 1,682 (Confidence interval (CI): one in 909 to one in 3,333)). Two mothers were incidentally picked up with IEM of carnitine uptake deficiency (CUD) and classic phenylketonuria respectively, and two false negative cases of Citrullinaemia type II (CIT type II) were notified. Incidence was increased to 1 in 1,376 if the two false negative cases were also included and it is higher than those in other countries or regions. Collectively, IEM cannot be claimed to be rare in Hong Kong.